	<!-- 载入页面头 -->
$('header').load( "header.html", function( response, status, xhr ) {
	$('header').html(response);
});
$('.copyright').load( "copyright.html", function( response, status, xhr ) {
	$('.copyright').html(response);
});
window.onscroll = function () {
	if (document.documentElement.scrollTop + document.body.scrollTop > 200) {
		document.getElementById("scrollto").style.display = "block";
	}else {
		document.getElementById("scrollto").style.display = "none";
	}
}